Additive for hydroconversion process and method for making and using same

ABSTRACT

An additive for hydroconversion processes includes a solid organic material having a particle size of between about 0.1 and about 2,000 μm, a bulk density of between about 500 and about 2,000 kg/m3, a skeletal density of between about 1,000 and about 2,000 kg/m3 and a humidity of between 0 and about 5 wt %. Methods for preparation and use of the additive are also provided. By the use of the additive of the present invention, the hydroconversion process can be performed at high conversion level.

BACKGROUND OF THE INVENTION

The invention relates to an additive used in catalytic processes forhydroconversion.

Hydroconversion processes in general are known, and one example of sucha process is that disclosed in co-pending and commonly owned U.S. patentapplication Ser. No. 12/113,305, filed May 1, 2008. In the processdisclosed therein, catalysts are provided in aqueous or other solutions,one or more emulsions of the catalyst (aqueous solution) in oil areprepared in advance and the emulsions are then mixed with the feedstock,with the mixture being exposed to hydroconversion conditions.

The disclosed process is generally effective at the desired conversion.It is noted, however, that the catalysts used are potentially expensive.It would be beneficial to find a way to recover this catalyst forre-use.

In addition, foaming and the like in hydroconversion reactors can createnumerous undesirable consequences, and it would be desirable to providea solution to such problems.

Hydroconversion processes in general for heavy residues, with highmetal, sulfur and asphaltene contents, cannot reach high conversions(more than 80wt %) without recycle and high catalyst concentration.

Additives which are known to be used to try to control foam in reactorscan be expensive and can chemically decompose in the reaction zone,potentially leading to more difficult by-product processing and thelike.

SUMMARY OF THE INVENTION

In accordance with the invention, an additive used in catalytichydroconversion processes is provided wherein the additive scavengescatalyst metals and also metals from the feedstock and concentrates themin a heavy stream or unconverted residue material which exits theprocess reactor, and this heavy stream can be treated to recover themetals. The stream can be processed into flake-like materials. Theseflakes can then be further processed to recover the catalyst metals andother metals in the flakes which originated in the feedstock. Thisadvantageously allows the metals to be used again in the process, or tobe otherwise advantageously disposed of.

The hydroconversion process comprises the steps of feeding a heavyfeedstock containing vanadium and/or nickel, a catalyst emulsioncontaining at least on group 8-10 metal and at least one group 6 metal,hydrogen and an organic additive to a hydroconversion zone underhydroconversion conditions to produce an upgraded hydrocarbon productand a solid carbonaceous material containing said group 8-10 metal, saidgroup 6 metal, and said vanadium.

Further, the additive can be use to control and improve the overallfluid-dynamics in the reactor. This is due to an anti-foaming affectcreated by use of the additive in the reactor, and such foam control canprovide better temperature control in the process as well.

The additive is preferably an organic additive, and may preferably heselected from the group consisting of coke, carbon blacks, activatedcoke, soot and combinations thereof. Preferred sources of the cokeinclude but are not limited to coke from hard coals, and coke producedfrom hydrogenation or carbon rejection of virgin residues and the like.

The additive can advantageously be used in a process for liquid phasehydroconversion of feedstocks such as heavy fractions having an initialboiling point around 500° C., one typical example of which is a vacuumresidue.

In the hydroconversion process, the feedstock is contacted in thereaction zone with hydrogen, one or more ultradispersed catalysts, asulfur agent and the organic additive. While the present additive wouldbe suitable in other applications, one preferred process is carried outin an upflow co-current three-phase bubble column reactor. In thissetting, the organic additive can be introduced to the process in anamount between about 0.5 and about 5.0 wt % with respect to thefeedstock, and preferably having a particle size of between about 0.1and about 2,000 μm.

Carrying out the process as described herein using the organic additiveof the invention, the organic additive scavenges catalyst metals fromthe process, for example including nickel and molybdenum catalystmetals, and also scavenges metals from the feedstock, one typicalexample of which is vanadium. Thus, the product of the process includesa significantly upgraded hydrocarbon product, and unconverted residuescontaining the metals. These unconverted residues can be processed intosolids, for example into flake-like materials, containing heavyhydrocarbon, the organic additive, and concentrated catalyst andfeedstock metals. These flakes are a valuable source of metals forrecovery as discussed above.

BRIEF DESCRIPTION OF THE DRAWINGS

A detailed description of preferred embodiments of the inventionfollows, with reference to the attached drawing, wherein:

FIG. 1 schematically illustrates a process according to the invention;and

FIG. 2 schematically illustrates a method for preparation of an organicadditive according to the invention; and

FIG. 3 schematically illustrates the benefit of using the additiveaccording to the invention;

FIG. 4 schematically illustrates the inner temperature profiles of thereactor when the additive of the invention is used;

FIG. 5 schematically illustrates the pressure differential profiles ofthe reactor relates to fluid-dynamic control when the additive of theinvention is used;

FIG. 6 schematically illustrates the pressure differential profiles ofthe reactor relates to phase distribution when is used the additive ofthe invention.

DETAILED DESCRIPTION

The invention relates to an additive used in catalytic hydroconversionprocesses of a heavy feedstock. The additive acts as a scavenger ofcatalyst and feedstock metals, and concentrates them in a residual phasefor later extraction. Further, the additive serves as a foam controllingagent, and can be used to improve overall process conditions.

A brief description of this hydroconversion process is given here, usingunit 200 in FIG. 1. In this hydroconversion process the feedstock,containing vanadium and/or nickel, is contacted with a catalystconsisting of one two or more emulsions (water in oil), containing atleast on group 8-10 metal and at least one group 6 metal, underhydroconversion conditions, which means, high hydrogen partial pressureand high temperature, and also in the presence of an additive which hasone purpose to concentrate the metals over its surface, making a metalrecovery process easier.

Within unit 200, conversion of the feedstock occurs, and the outflowsfrom unit 200 include a product stream including an upgraded hydrocarbonphase which can be separated into liquid and gas phases for furthertreatment and/or feeding to a gas recovery unit as desired, and aresidue containing the additive which can be solidified or separated ina stream rich in solids, to be fed to a metal recovery unit, andunconverted vacuum residue, which can be recycled.

The feedstock for the hydroconversion process can be any heavyhydrocarbon, and one particularly good feedstock is vacuum residue whichcan have properties as set forth in Table 1 below:

TABLE 1 Properties Unit Distillation LV % ASTM D1160 IBP ° F. 600-900Viscosity@210° F. cst <80000 API — 1-7 Sulfur wt % 3-8 Nitrogen wt %  <2 Asphaltenes wt % 15-30 Conradson Carbon wt % 15-30 Metal (V + Ni)wtppm  200-2000

Alternative feeds include but are not limited to feeds derived from tarsands and/or bitumen.

For a vacuum residue (VR) feedstock, this can come from a vacuumdistillation unit (VDU) for example, or any other suitable source. Othersimilar feeds can be used, especially if they are of a type that can beusefully upgraded through hydroconversion and contain feedstock metalssuch as vanadium and/or nickel.

As indicated above, the additive is preferably an organic additive suchas coke, carbon black, activated coke, soot, and combinations thereof.These materials can be obtained from any of numerous sources, and arereadily available at very low cost. The organic additive can preferablyhave a particle size of between about 0.1 and about 2,000 μm.

The catalysts used are preferably a metal phase as disclosed inco-pending U.S. Ser. No. 12/113,305. The metal phase advantageously isprovided as one metal selected from groups 8, 9 or 10 of the periodictable of elements, and another metal selected from group 6 of theperiodic table of elements. These metals can also be referred to asgroup VIA and VIIIA metals, or group VIB and group VIIIB metals underearlier versions of the periodic table.

The metals of each class are advantageously prepared into differentemulsions, and these emulsions are useful as feed, separate or together,to a reaction zone with a feedstock where the increased temperatureserves to decompose the emulsions and create a catalyst phase which isdispersed through the feedstock as desired. While these metals can beprovided in a single emulsion or in different emulsions, both wellwithin the scope of the present invention, it is particularly preferredto provide them in separate or different emulsions.

The group 8-10 metal(s) can advantageously be nickel, cobalt, iron andcombinations thereof, while the group 6 metal can advantageously bemolybdenum, tungsten and combinations thereof. One particularlypreferred combination of metals is nickel and molybdenum.

One embodiment of a suitable hydroconversion process is that disclosedin a simultaneously filed US patent application bearing attorney docketnumber 09-289-2, which is incorporated herein by reference. In such aprocess, more than the two mentioned metals can be used. For example,two or more metals from group 8, 9 or 10 can be included in the catalystphases of the emulsions.

The catalyst emulsion(s) and heavy feedstock can be fed to the reactorspreferably in amounts sufficient to provide a ratio of catalyst metalsto heavy feedstock, by weight, of between about 50 and about 1,000wtppm.

Hydrogen can be fed to the process from any suitable source.

The reaction conditions can be as set forth in Table 2 below:

TABLE 2 Reactor Pressure 130-210 barg Reactor Temperature 430-470° C.Conversion Rate 80% or more

Then according to the invention, in a slurry feed process, the unit 200receives a vacuum residue (VR). The additive particles can be added tothe VR, in a concentration between 0.5-5 wt % respect to the feedstock,and agitated. The agitated slurry is preferably pumped up to an elevatedpressure, preferably over 200 barg, by high-pressure slurry pumps. Theslurry is also heated to an elevated temperature, preferably over 400°C. Upstream, catalyst emulsions, sulfur agent and hydrogen are injectedunto the slurry feed. After a slurry furnace for heating the slurry,more hydrogen can be added if needed.

The total mixture of VR, organic additive, catalyst emulsions, sulfuragent and hydrogen are introduced into the reactor and deeplyhydroconverted into the desired lighter materials. Most of thehydroconverted materials are separated as vapor in a High Pressure HighTemperature separator, and the vapor can be sent to a later unit forhydrotreating and further hydrocracking as needed.

In the meantime, the bottom product of the separator, in the form of aheavy slurry liquid, can be sent to a vacuum distillation unit torecover, under vacuum, any remaining lighter materials, and the finalremaining bottom residue which is the unconverted residue could be sentto different type of processes where it can be converted into a solidmaterial.

Typical yield from a specified feedstock is set forth in Table 3 below:

TABLE 3 Weight Feed Stock Vacuum Residue 100 Catalyst Emulsions +  8-10Coke Additive Flushing Oil (HGO) 2.6-3.6 Hydrogen 1.8-3   Feed Total112.4-116.6 Products C₁-C₄ 7-9 H₂O 1-2 H₂S + NH₃ 3.4-4.0 Naphtha 16-20Middle Distillates 28-34 VGO 40-45 Total Products (excl. Flakes)95.4-114  Unconverted Residue or Flakes 17-9 

One of the units for converting the bottom residue into a solid materialcould be a flaker unit. The resulting flakes can advantageously have thefollowing composition:

TABLE 4 Physical state and appearance Solid brittle API −5-(−14.4) ColorBrilliant Black Volatility Negligible at room temperature Boiling PointGreater than 500° C. Density at 15° C. (kg/m³)  900-1350 TolueneInsoluble wt % 15-40 Asphaltenes (IP-143) wt % 30-50 preferably 30-40Heptane Insoluble (wt %) 28-50 Carbon Residue (Micron Method) wt % 22-55Molybdenum wtppm 1500-5000 Vanadium wtppm 1400-6500 Nickel wtppm 50-3000 Carbon Content wt % 85-93 Hydrogen Content wt % 5-9 RatioCarbon/Hydrogen 10-17 Total Nitrogen wt %  1.-2.5 Sulfur wt % 2.2-2.7VGO (%)  6-14 Ash wt % 0.2-2.0 Volatile Matter wt %: 61.4 60-80 HeatingValue BTU/Lb 15700-16500 Moisture wt %:   0-8.00 Hardness index (HGI)50-68 Softening Point ° C.: 110-175 Kinematic Viscosity at 275° F. cSt13,000-15,500 Flash Point ° C. 300-310 Pour Point ° C. 127 % OFF (wt %)T (° C.) Simulated distillation (D-7169) IBP 442.9 1 445.6 5 490.7 10510.9 15 527.0 20 541.9 25 557.7 30 574.9 40 618.9 50 668.5 58 715.0

These flakes, containing remaining organic additive and also thecatalyst metals and metal from the feedstock which is scavenged by thecatalyst according to the process of the present invention, canthemselves be provided to consumers as a source of useful metals, or canbe used as fuel, or can be treated for extraction of the metals forre-use as process catalyst and the like.

Of course, the metals to be recovered include not only the catalystmetals used in the process, but also certain metals such as vanadiumwhich are native to the feedstock.

As set forth above, an organic additive is an important aspect of thehydroconversion process disclosed in the simultaneously filed US patentapplication bearing attorney docket number 09-289-2. This additive canbe obtained from numerous sources, for example coke from many sourcesincluding hard coals, carbon blacks, activated coke, soots fromgasifiers, cokes produced from hydrogenation or carbon rejectionreactions, virgin residues and the like. It should be appreciated thatthese numerous sources allow preparation of the additive from readilyavailable and affordable raw materials. A method for preparing theadditive from such raw materials is discussed below, and the end resultfor use as an additive according to the invention preferably has aparticle size of between about 0.1 and about 2,000 Am, a bulk density ofbetween about 500 and about 2,000 kg/m³, a skeletal density of betweenabout 1,000 and about 2,000 kg/m³ and a humidity of between 0 and about5 wt %. More preferably, the particle size is between about 20 and about1,000 μm.

Referring to FIG. 2, a method for making the additive of the presentinvention is illustrated. The starting raw material can typically be asdescribed above, and can have properties such as bulk density of betweenabout 500 and about 2,000 kg/m³, a humidity of between about 5 wt % andabout 20 wt %, a hardness of between about 20 HGI and about 100 HGI anda maximum particle size between about 5 cm to about 10 cm. This rawmaterial is preferably first fed to a primary milling station 61 wherethe material is milled so as to reduce the particle size by an order ofmagnitude of preferably about 10. These preliminarily milled particlescan have a particle size typically between about 20 mm and about 20 μm,and are fed to a drying zone 62. In the drying zone, the particles areexposed to a stream of air which removes humidity from the particlespreferably to less than about 5% wt. The resulting dried particles arethen fed to a primary classification zone 63, where the particles areseparated into a first group which meets a desired particle sizecriteria, for example less than or equal to about 1000 μm, and a secondgroup which does not meet this criteria. As shown, while the acceptableparticle sized material of the first group is fed to a secondaryclassification zone 66, the second group needs additional milling and ispreferably fed to a secondary milling station 64 where it is furtherground or otherwise mechanically treated to reduce the particle size.The further milled product is fed to another classification zone 65,where particles which do now meet the criteria are fed back to combinewith those that initially met the criteria, and those which still do notmeet the criteria are recycled back through secondary milling station 64as needed.

From secondary classification station 66, some particulate material willnow be found that does not meet the desired criteria, and this materialcan be separated off and fed to an agglomeration station 70, where theparticles are granulated to obtain particles with a higher diameter bymeans of a mixture of chemical substances. In the meantime, theparticles which meet the criteria at station 66 are now fed to a heattreatment station (67) where they are exposed to a stream of heated airto bring their temperature up to between about 300 and 1,000° C., underthis conditions a porogenesis process takes place. The heated particlesare then fed to a cooling station (68) where they are cooled, in thisinstance with a stream of water cooled air. The resulting particlesshould have a temperature of less than about 80° C.

The heated and cooled particles can now be fed to one moreclassification zone 69 to again separate out any particles which do notmeet the desired particle size criteria. Such particles that do not passcan be fed to agglomeration zone 70, while those which do pass can beused as the additive according to the invention.

The organic additive can ideally be used in an amount between about 0.5and about 5 wt % with respect to the feedstock, and in this amount canserve both to scavenge catalyst and feedstock metals and control foamingin the reactor to provide more stable and efficient conditions in thereactor.

In the reactor, when using the additive of the present invention, thereaction can advantageously be carried out at a gas velocity of greaterthan or equal to about 4 cm/s.

These advantageous process conditions can produce a hydroconversion withan asphaltene conversion rate of at least about 75 wt % and a Conradsoncarbon conversion of at least about 70 wt %, and these rates aredifficult or impossible to be obtained otherwise, using conventionaltechniques.

Turning to FIG. 3, two views are shown of reactors undergoing ahydroconversion process. In the left side view, a reactor is shown wherethe process is being carried out without any additive according to theinvention. As shown, the reaction is a biphase reaction, and has a lowerportion with only liquid and an upper portion, approximately 60-70 v %,of foam and gas. The right side view of FIG. 3 shows a similar reactorwhen operated with the additive of the present invention, and shows thatfoam is now much better controlled, with 70-80 v % of the reactor beingfilled with a liquid and solid phase, and an upper 20-30 v % of thereactor containing gas.

The foam reduction is caused by breaking the bubbles, therebydiminishing diffusion problems by providing a better contact between gasand liquid. These conditions, obtained by using the additive accordingto the invention, lead to much more effective conversion, a bettertemperature control and a reduction of unwanted hot spots.

During the course of the hydroconversion reactions in unit 200, theheaviest components of the feedstock tend to become insoluble in thelighter fractions generated by the reaction itself. High temperaturespromote polymerization and condensation reactions of aromatic clustersand when difference between the solubility parameters of the twopseudo-components (asphaltenes and maltenes) approaches a criticalvalue, the system gives rise to the appearance of sediments andtherefore, to asphaltene precipitation and coke formation. This loss ofresidue stability at very high conversion level can be controlled byeffect of the coke and asphaltenes scavenger of the organic additive.Thereby, a maximum conversion is achievable. This scavenger effect isshow in example 1.

EXAMPLE 1 Coke/Asphaltene Scavenger Capability

This example illustrates asphaltenes, coke and/or polycondensed ringaromatic compounds catching capability of the carbonaceous additive.

In this example, Petrozuata petroleum coke was used to generate thecarbonaceous additive, this coke comes from delayed coking process. Thiscoke was thermally treated through a moderate combustion process(porogenesis) with air to generate some porosity and surface area. Theparticle size was adjusted in the range of 200-900 μm, following thescheme represented in FIG. 2, the carbonaceous additive was generatedand the following experimentation was effected.

Table 55 shows Petrozuata coke composition.

TABLE 5 Element wt % Carbon 86.6-88.9 Hydrogen 4.2-4.7 Sulfur 4.4-4.8Vanadium 0.20-0.22 Nickel 0.30-0.54 Iron 0.106 Ashes 0.21-0.52 Volatiles 9.9-12.0

10 g of Merey/Mesa vacuum residue (VR) were mixed with 100 ml oftoluene; the mixture was placed in stirring to dissolve the VR. Afterthat, 120 ml of n-heptane were added, agitation was maintained for 10min. Then the carbonaceous additive was added in an amount of 1.5 wt %to RV. It was subsequently agitated for 24 h. Finally, the sample wasfiltered, washed with n-heptane and the carbonaceous additive was driedin a stove for 4 h. After that, the cooled solid obtained was weighed.The amount of asphaltenes retained per gram of additive used wascalculated according to the initial amount of additive used.

Table 6 shows pore size, superficial area and asphaltene scavengercapability of carbonaceous additive.

TABLE 6 Pore Size(Å) 15.6 Superficial Area (m²/g) 270 Asphaltenesscavenger capability (wt %) 13

EXAMPLE 2 Metal Scavenger

This example illustrates metal scavenger capability of the carbonaceousadditive.

In this example, flake like material containing the unconverted vacuumresidue and the remaining organic additive was used to quantify themetal content and metal mass balance of the hydroconversion process.

In this example the remaining organic additive was separated by using adesolidification procedure with toluene as solvent. Following the schemerepresented in FIG. 1, flakes where generated and the followingexperimentation was effected.

50.00 g of flakes were dissolved in 350 ml of hot toluene, this mixturewas then centrifuged at 1500 rpm for 20 minutes to separate theunconverted residue of the additive. The solids were decanted and washedusing toluene Soxhlet extraction, which is a continuous extractionmethod whereby fresh solvent continuously flows through the compound tobe extracted. After that, the solids were dried in a vacuum oven for twohours at 130° C. The unconverted vacuum residue was recovered byevaporating the toluene. In this example the amount of dried solids was4.9 g.

Finally, the metal content in solids and in the unconverted vacuumresidue was determined by inductively coupled plasma (ICP) coupled to aOES.

Table shows Mo, Ni and V content of flakes, additive and the unconvertedvacuum residue.

TABLE 7 Mo Ni V Fe Flakes analyses (wtppm) 1977 1183 2103 459 DriedSolid Additive analyses 3812 2790 3984 822 (wtppm) Calculated metal indried solids^(a) 1868 1367 1952 403 (wtppm) Metal recovery ratios^(b)(wt %) 94.5 115.6 92.8 87.8 Non-converted vacuum residue <5.0 65 65 <5.0(wtppm) Experiment conditions Solvent Toluene Measured flakes (g) 10.00Measured dried solids (g) 4.90 ^((a))Calculated Metals in Dried Solids =Dried Solids Analysis * Measured Dried Solids (g)/Measured Flakes (g).^((b))Some yields above 100% - within experimental error.

EXAMPLE 3 Fluid-Dynamic and Temperature Control

Following the scheme represented in FIG. 1, the followingexperimentation was effected.

The test was carried out using sample of vacuum residue (VR) of Canadianoil, prepared from Athabasca crude.

This VR was fed into a slurry bubble column reactor without anyinternals, with a total capacity of 10 BPD, with a temperature controlbased on a preheater system and cool gas injection. This reactor has alength of 1.6 m and a diameter of 12 cm.

For this test the reactor was operated at 0.42 T/m³h. Three seriallyconnected vertical slurry reactors were used during this test. Theconditions were maintained for 11 days.

Conditions are summarized in Table 8.

TABLE 8 Feedstock characteristics API density (60° F.) 2.04 Residue 500°C.⁺ (wt %) 97.60 Asphaltenes (insolubles in heptane) (wt %) 21.63 Metalcontent (V + Ni) (wtppm) 462 Sulfur (wt %) 6.56 Process variables WSHV(T/m³h) 0.42 Feedrate (kg/h) 24 Total pressure (barg) 169 Reactoraverage temperature (° C.) 453 Gas/Liquid ratio (scf/bbl) 34098 Gassuperficial velocity (inlet first reactor) (cm/s) 7.48 Particle size(μm) 200-300 Organic additive concentration (wt %) 1.5 Nickel catalystconcentration (wtppm) 92 Molybdenum catalyst concentration (wtppm) 350

During this test the inner temperatures of the first reactor wasmeasured at 12 different highs, having as a result the profile shown inFIG. 4.

In FIG. 4 it is possible to observe the effect of the additive over thetemperature. At the beginning of the test the profile varies between2-4° C., at intervals of 10 hours, for the same high, it presents anunstable behavior. After the additive has reached a stable concentrationinside of the reactor the profile varies, at most, less than 2° C. andthe behavior is appreciably more stable.

The pressure differentials were measured for the three reactors,obtaining the profile shown in FIG. 5.

This profile shows that at around the point of 100 hours on stream thethree reactors have a stable concentration of solids, which isnoteworthy since the pressure differentials show an almost linearbehavior since the first hour. This is in concordance with thetemperature profile, which has a stable behavior since the same firsthour.

This evidences that the additive gives a fluid-dynamic control, whichalso acts, at the same time, as a temperature control.

EXAMPLE 4 Foam Control and Phase Distribution

Following the scheme represented in FIG. 1, the followingexperimentation was effected.

This example was carried out using a vacuum residue (VR) of Venezuelanoil, Merey/Mesa.

This VR was fed into a slurry bubble column reactor without anyinternals, with a total capacity of 10 BPD, with a temperature controlbased on a preheater system and cool gas injection.

For this test the reactor was operated at 0.4 T/m³h (spatial velocity),using three serially connected vertical slurry reactors. The plant wasin continuous operation for 21 days.

Conditions are summarized in Table 99.

TABLE 9 Feedstock characteristics API density (60° F.) 5.0 Residue 500°C.⁺ (wt %) 96.3 Asphaltenes (IP-143) (wt %) 19.3 Metal content (V + Ni)(wtppm) 536 Sulfur (wt %) 3.28 Process variables WSHV (T/m³h) 0.4Feedrate (kg/h) 24 Total pressure (barg) 170 Reactor average temperature(° C.) 452.1 Gas/Liquid ratio (scf/bbl) 40738 Gas superficial velocity(inlet first reactor) (cm/s) 6.4 Particle size (μm) 212-850 Organicadditive concentration (wt %) 1.5 Nickel catalyst concentration (wtppm)132 Molybdenum catalyst concentration (wtppm) 500

During the test, pressure differentials were measured in the threereactors, giving the profile shown in FIG. 6.

As this profile shows, the time to fill each reactor was about 15 hours,this is given by the time at where the pressure differential of thereactor has a measure more likely to be stable. In this profile it canbe seen that the first reactor reaches the stable measure at around 15hours and after the first reactor is filled up, the second reactor takesaround another 15 hours to reach the stable measure, and the samebehavior is shown by the third reactor.

After the fill up of the reactors the total time for stabilization isaround 75 hours.

The foam reduction can be seen as the rise on the pressure differentialsas a consequence of an increase in the liquid quantity due to solidconcentration inside of the reactors.

With the pressure differentials it is possible to calculate the phasedistribution for the first reactor. This differential was calculated attwo conditions: 0 hours and during the test, as an average after thestabilization time (75 hours), the results are summarized in Table 1010.

TABLE 10 Without With Conditions additive additive Hours on stream 0After 75 h Temperature (° C.) 380 449 ΔP in the first reactor (mbar)26.5 59.85 Liquid density (kg/m³) 804.6 760 Liquid holdup 0.34 0.69 Gasholdup 0.66 0.28 Solid holdup 0 0.03

As shown in Table 10, the liquid holdup in the reactor using theadditive increases by a factor of 2, which is related to a higherconversion because this improves the reaction volume.

The above examples demonstrate the excellent results obtained using theadditive in the hydroconversion process according to the invention.

The present disclosure is provided in terms of details of a preferredembodiment. It should also be appreciated that this specific embodimentis provided for illustrative purposes, and that the embodiment describedshould not be construed in any way to limit the scope of the presentinvention, which is instead defined by the claims set forth below.

1-30. (canceled)
 31. An additive for hydroconversion processes, comprising a solid organic material having a particle size of between about 0.1 and about 2,000 μm, a bulk density of between about 500 and about 2,000 kg/m³, a skeletal density of between about 1,000 and about 2,000 kg/m³ and a humidity of between 0 and about 5 wt %.
 32. The additive of claim 1, wherein the particle size is between about 20 and about 1,000 μm. 